The event takes place Dec. 29 at MGM Grand Garden Arena in Las
Vegas and is headlined by a heavyweight title rematch between
reigning champion Junior dos
Santos against former kingpin Cain
Velasquez. Verbal agreements are in place for the Brunson-Leben
showdown, according to the announcement.

Brunson, 28, began his career a perfect 9-0 before stumbling in his
two most recent outings, first dropping a split decision to
“Ultimate Fighter” Season 3 winner Kendall
Grove before being knocked out in just 41 seconds by former
Strikeforce champion Ronaldo Souza
this past August. A representative of Jackson’s MMA, Brunson earned
four victories last year, three of which came under the Strikeforce
banner.

An alumnus of the original “TUF” series, Leben is known for his
knockout power and ability to absorb punishment. Though the
32-year-old posted a trio of wins in 2010, he has lost two of his
last three fights, most recently suffering a second-round technical
knockout to Mark Munoz in
November 2011. “The Crippler” tested positive for painkillers
following that defeat, prompting the UFC to suspend the fighter for
one year.

Vemola, 27, suffered a fractured cheekbone in training that caused
his withdrawal. The Czech’s clash with Leben would have marked his
third as a UFC middleweight and his fifth appearance overall in the
Octagon. Vemola, who debuted in the UFC has heavyweight, holds a
2-3 promotional record, recording wins over Seth
Petruzelli and Mike
Massenzio in his two-plus years with the organization.